Process of manufacturing portland cement.



INVENTC- alla vz SHEETS-SHEET' 1.

4 TATENTEIU DEC. 5, 1905. E. H. HURRY C E. J. sEAMAN. 1 PROCESS CE.MANUFACTURING PORTLAND CEMENT.

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Np. 806,146] y PATENTBDDm, 1905. y E. H. .HURRY & H. J. SEAMAN.

' PROCESS OF MANUFACTURING PORTLAND CEMENT APPLICATION FILED JULY17,1900.

2 SHEETS-SHEET 2.

. A' wnNEsssr' I i ."V m5 Y ff BY ATTORNEYA 1 EDWARD HENRY HURRY, OF`HETHLRHRM,.AND 'HARRY JOHN 'SEAMAN OF OAT-ASAUQUA, PENNSYLVANIA,

Pnocslsss'v oF MANUFACTUMNG PORTLANDJOEMENT.,

" To @ZZ whom ifm/ay concern.'

Be it known-that We, EDWARD HENRY HUR- v RY, a'subject of the Queen ofGreat Britaini -clinken residing at Bethlehem, in the county of North#ampton,v and HARRY JOHN SEAMAN, a citizen of the United States, residingat Catasauqua,

county of Lehigh, State of Pennsylvania, have jointly .invented certainnew and useful Im#` provements 1n Processes of -lVlanufacturing .1o.

Portland Cement, of which ythe following is af specilication. y

The object of the invention is to decrease the cost of manufacturingPortland cement of high quality, 1 i In manufacturing Portland lcementaccord-y ing'to the present invention we ksubject the raw materialscontaining lime, silica, and:`

aluminay to vsuch a'tempera'ture while in [dii rect contact with thefuel that the chemicalv reactions desired between theconstituents arefobtained and the resulting products fused toy liquidity. We prefer tocarry on this operation 1n a reducing atmosphere and under a5pressurefgreater than atmospheric presjsuiiei 'eral important advantagesare attained', Nearly all argillaceous materials available for thecommercial manufacture of Portland cement contain a varying percentageyof ironI the processes heretofore in use staining prop` l erties oftenmost undesirable. ^Byfusion in 'ar lreducing yatmosphere this '.ironoxidcan bei 'substantially'allreduced to metallict iron and; rseparated bygravity from themolten cementfv lmass entirely or substantiallyfree'froxn iron may therefore be tapped off,"cooled, and pul- 'Verized,theresulting product bei'ng Portland cement of high quality andsubstantially free from iron; 'The lower portion of the molten ymass maybe separately drawn off and applied to suchl uses after furthertreatment, if desired, vas may be expedient.l f f y It is wellVl'nown'that up to a certain limit an increase of the percentage of'lime con- 'tainedv in the lraw materials' and 'the' resulting Portlandcement materially increases the strength ofisuchpe'ment; vbut'infthemethods of manufacture hitherto in'use it'has not been 'commerciallypossible to push this advantage to its full limit, it-being found thatwhen the lcontent of. lime inithe-'jPortland cement so manufacturedexceeds about sixty-two per- Speciiication lof 'Letters Patent.Application filed July 17,1900. Serial No. 23,942.

We find that by this mode of procedure sev`` oxid, which gives thecement manufactured by;

The upper portion ofthe molten- Patente.diDec.v 5, 1905.

cen'tum it is'very liable` after being used to crack, blow fordisintegrate, such result being dueto the presence of lime which has Ynot entered into thorough chemical combination with the otheringredients, of our improvedprocess, however, the percentage of lime maybe increased, when the proper ratio exists between the containedsilica-and alumina, to as highas sixty-seven per cent. without danger ofdisintegration of 'the cement after use; The very high ternperature usedand the very intimate mixing secured by fusion provide conditions sofavor- 'able to the attainment of the requisite chemical combinations'that the liability of uncombined'or loosely-combined lime occurring inthe product is minimized.A

A practical plan or mode of practicing tliev invention whichwe deem mosteiiicient vand vdesirable for various reasons is to introduce the"above-named raw materials mixed carbonaceous fuel at the top or upperpartof 'an`upright furnace having a closed 'bottoiij or hearth with twotap-holes one above theoth'er,

i one fo'rdrawing olf .the upper portion i molten cement material,,fromwhich `iron isseparated andthe' lower one for tappingi olf thelowerprtion of'- the',y moltenunass containing` the ironi-Blasts o fcompressed. air

are introduced inisuitable vol'ume'in thelower portion of the furnaceaboveI tletap-hol'es, as

li`n`-ordinary.'blastjfurnace practice, :and the resulting hightemperature and reducing atmosphere produce the results above stated.

If we mix the fuel andl the raw cement materials-'n'am'ely, carbonate oflime and clay or argillaceousmaterial containing alumina and silica inthe natural state in which they come from the quarries (b reakingthem upinto pieces of suitable'sizel-the carbonate of lime will giveup itscarbonio acid, which will pass outof the furnace mixed with carboniovoxid andthe other gases. arbonic' acid may be thus disassociatedfrom'the carbonate of lime, or this may be' accomplished'by'apreliminary roasting of -the carbonate of lime, Pandineithercase we areenabled to omit 'the By the use IOO plan usually heretofore practiced ofiirstrev'd'ucing the raw materialsy to the'form ola "iinely-levigatedslurry, then drying the slurry and breaking it lp or molding the slurryinto fluinps'for fbiicks, drying them,v and then in either case burningthem ina klln, as 1n one well-known process,or of grinding the dry rawmaterials together to a fine powder, which is then burned in a rotaryfurnace according to another well-known mode of operation, or of dryingand burning wet slurry in the same operation in a rotary kiln. We maytherefore eliminate substantially the whole or the larger part of thecost (both in labor and in plant) of.

Y liminarily driving the carbonio acid off from the carbonate of lime orof initially mixing the carbonate of lime with the other cementmaterials and fuel we may effect the fusion or melting of the cementmaterials in an area or zone of the furnace wherein a pressureconsiderably above that of the atmosphere is maintained-say a pressureof from fifteen to twenty pounds per square inch above theatmosphere-such pressure being primarily due to the air-blast andmaintained, according to one way of practicing our process, by theresistance which the column of materials and fuel in the furnace opposesto the passage through it of the products of combustion. Ve mayconveniently attain this end by making the height of the furnace suchthat with the blast-pressure employed the desired pressure may bemaintained in the lower region or zone of the furnace where the highesttemperature exists. 1f the carbonate of lime of the raw materialsl hasbeen introduced without preliminary calcination, as it descends in thefurnace, and so gets raised in temperature, its

carbonio acid will be liberated and passingthrough the superimposed fuelwill be more or less carbonized to carbonic oXid. Should the conditionsbe such that there is not a sufliciently complete carbonization of thecarbonic acid and it is desired to utilize the carbonic oXid produced inthe furnace, the gases may be passed through incandescent coal or coke.Ordinary producers, such as are used for the production of water-gas,may be utilized for this purpose and an extremely rich producer-gas thusobtained which may then be eiciently burned for the heating of theblast, the raising of steam, or for other useful purpose.

Where the carbonate of lime is to be preliminarily calcined, all of thecarbonio oxid and otherl products of combustion from the furnace may bepassed through the carbonate of lime in the calcining chamber or furnaceand there burned, air being introduced to support such combustion of thegases, and substantially all of the heat of said products of combustionbe utilized in driving olf carbonio acid from the carbonate of lime ofthe raw materials and heating the resultant lime with or without theother raw ingredients, the

calcining-chamberbeing made of such height or dimensions as to lenditself economically to this operation, or a part only of the carbonicoxid may be utilized for preliminar-ily calcining the carbonate of limeand the residue be diverted and burned for raising steam and heating theblast.

Another mode of practicing our invention according to the plan ofmelting the cement materials in the presence of a high pressure is tomaintain the pressure within the furnace by throttling thev outlet ofthe products of combustion, as by means of a loaded valve or anadjustable valve or plug, and in this case we may preliminar-ily calcinethe carbonate of lime by utilizing the carbonic oXid from the furnace inwhole or in part, and where but a part of it is employed for thispurpose the residue may be diverted and burned for raising steam andheating the blast.

Where we maintain the desired high pressure in the furnace by checkingthe egress of the products of combustion, as above suggested, we maywith proper regulation of blast-pressure and egress of products ofcombustion maintain any high pressure that may be desired for thepurposes of the operation, and when operating in this way we are enabledto practice our invention according to another plan or mode ofoperation, which is as follows:

When carbonate of lime is heated to a temperature of about 1,000OFahrenheit, its contained carbonio acid is given off as gas, theremaining solid being caustic lime. If, however, tlie carbonate of limebe heated in a vessel in which a constant pressure materially in excessof that of the atmosphere is maintained, the carbonate of lime will fuseand run,

and if the source of heat be then withdrawn and the vessel and contentsallowed to cool the carbonate of lime will be found as a stonelikesubstance of the form of the interior of the vessel. 1f, however, whenthe carbonate of lime is fused the source of heat be not withdrawn, butthe heating continued, a temperature will be attained at which theliquid carbonate of lime gives off its carbonio-acid, the temperature atwhich this occurs being dependent on the pressure in the vessel, and ifthe carbonio acid be drawn off as produced, so that the pressure doesnot increase, the carbonate of lime may be thus entirely calcined. As bythe combustion of the fuel, aided by a heated blastand the high pressureof from twenty to thirty-tive pounds per square inch, a temperature offrom 3,5000 to 4,000O Fahrenheit may be maintained in the hottest zoneof the furnace while constantly removing the carbonio acid from the zonein which it is produced along with the products of combustion, we mayeliminate all or substantially all the carbonio acid from the carbonateof lime.

The furnace having been charged with the raw cement materials (thecarbonate of lime IOO IOS

IIO

of which has not been calcined) mixed with,

the fuel when the liquid carbonate of lime gives up its carbonic acidinthe manner a'bove described, the resulting caustic lime is inimmediate proximity tothe silica and alumina` of the argillaceousingredients, all having been raised to such temperature as to cause ithe chemical union of the lime with the sil-ica and aluminadirectly thecarbonate of lime is freed from its carbonic acid. `In this way thebasic and acid ingredients are brought together in a manner" mostfavorable to mutual iuxing-and they fusion of the" product is cor'-respondingly facilitated.- In practicing this mode of operation it willbe'seen that the car'- bonic acid is given off from kthe carbonate oflimeatza zone in the furnace which is overlaid with a thickA bed ofincandescent fuel, and the passage of the carbonic-acid gas throughUnder allthe conditions or in all the ways -this incandescent carbon issufficient to carboriiZe the 'gas to carbonic oxid, and thus a rich`combustible gas is produced bythe furously-rnentioned.V

nace for utilizatio`n for thev purposes previof practicingo'ur processthe cement materials willbe melted at a "high temperature and in contactwith the fuel. i Accordingto the con- A ditions of thek operation asufficient quantity of lfuel will be mixed with the cement matel rialstoefecttheresults here'inbefore stated,

and "when 'afuel containing ash is usedfthe' quantities ofthe respectivecementmaterials will, or should be, proportioned to the amount of fuelemployed, as is well understood-,that

is to"say,'suiiicient lime should always be supplied to combine with thesilica and alu-V mina of the ash, so that the qualtity of the resultantcement will be in no way impaired by the production of ash from the fuelin the progress-of the operation. f

Where a pressure materially above that of the atmosphere *is maintainedin the melting zone or region of thegfurnace,ithe pyrometric valueorintensity of the heat due to the r combustion of the fuel isconsiderably greaterV than where combustion'of such fuel occurs' in thepresenceof a'pressure equal to that of the atmosphere,'or,thereabout,and it is thus:

possible toobtain an extremelyv high temperaproducts of combustion isVunobstructed at the-top of the furnace, a suiicient pressure may'readilybe maintained, as before suggested', by regulating thef height of thecolumn of material in the'furnace. i' It wouldbe entirely feasible toinl this way maintain with fair regularityV inv the melting Zone'apressure of from ten to twenty pounds per-square inch abovetheatmosphere, the temperature and pressure gradually falling as the topof the column is approached where the gases or productsof combustion mayvleave the furnace substantially at,or at-least verylittle above,atmospheric pressure. -When operating in this way, the carbonic acidwill be eliminated above the zone of highest pressure and temperatureand noffusion of the carbonate of lime will occur. The height ofthecolumn of material required to maintain in the zone of fusion a desiredpressure will .of course depend upon thesize and nature of the pieces offuel and cement material. 'When the same are in small'pieces, andespecially if one of the materials be of a clayey nature, a pressure offromrten to fteen pounds pery square inch-may be retained in the fusionzone-by a superimposed column of material` of from sixty to eighty feetin height. Where, however, the outlet for the products of combustion isvso regulated as Ato maintain a considerable pressure at theoutlet and afurnace of less height is employed,

as in the lastl plan abovedescribed of practicing our invention, thedifferences in pressurerand temperature between the upper end of thefurnace 'and the lower part or the zone v of fusion would beless; but,as above stated, t

thetemperature and conditions would be such" that the carbonicacid wouldnot only be eliminated from the carbonate of, lime but would also in thepresence of ythe highly.incandes` Y ycent fuel be converted intocarbonic oxid.A

In the'accompanying drawings, Figure lis an elevatlolnwith: the furnace1n sectiomscmewhat dlagrammatic 1n character,` illustrating ICO oneorganization-for practicingour process.

Fig. 2l is a vertical section showing the upper part of a furnace ofasomewhat different construction, the lower part of which, as well .as

shown in FigflyFig. 3, a vertical sectionf showingthe upper part offanother constructlon of furnace -for practlcln'g our invention, f

the lower part of which-may be thesame as is illustrated in Fig-1. jFig. 4 is avertical section showing the upper "part-of stillanother lconstruction of furnace, thelower'portion ofwhich may' also be 'of theconstruction'-illustrated in'gFig. 1.

Figfl'i shows a furnace. analogous in. con- "l struction :to an ordinaryblastfurnace. It

consists-substantially of a verticall stackcomposed of' an exterior ironshell A and a lining of refractbry material B. At the topthere'are anoutlet C forthe products of combustion, a charging-platform, and-.afeeding-bell D, normally closing nthe top ofthe furnace. E is' thehearth and crucible, having an upper taphole@ anda lower tap-hole fe'. frepresents The mol- 10S the apparatus associated with it,may bevas tenmaterial from the upper tap-hole e may be run into a ear Gr, where it issubjected to spray of lwater from the nozzle g, which effects itscooling and disintegration. 'Ihe car may be drawn up the inclinedplatform or track by the engine H and the cooled disintegrated cementmaterial dumped into the hopper I, which may deliver it to thegrindingmill K.

Fig. 2 shows the top of the furnace modified as follows: Axially abovethe top of the stack is a chamber L, to which the cement material isdelivered from the charging-platform and which may not have any bell orclosing device. At the point where the top of the furnace is contractedand merges into the v.er tical chamber L there is a lateral chamber orbifurcation M, which may be normally closed at the top by a bell M. Thefuel is fed as required to the chamber M and mixes with the cementmaterial at the top of the main stack or body of the furnace, at orabout which point there are one or more twyers or air-blast inlets g,connected with the air-blast pipe F. The mixed carbonic oxid and airburned in the chamber L effects the disasseciation of carbonic acid fromthe carbonate of lime. In either of these constructions thefurnace-stack should be of appropriate height, as hereinbeforesuggested.

In Fig. 3 the top of the furnace is normally closed by a bell D, as inFig. l, and the outlet C for the products of combustion leads into aninclosed chamber 0, its outlet being formed for a valve-seat coperatingwith a fire-clay valve c on a vertical stem c2, passing through abushing in the chamber and weighted, as indicated at c3. ducts theproducts of combustion or carbonic oxid from the chamber e to the stoveand boiler direct, the construction here illustrated providing for thepreliminary calcination of the carbonate of lime, as follows: A pipe O,connected with the pipe c4, is provided with a suitable cock or valve 0and connected with one or more nozzles o', entering a vertical roastingor calcining chamber P at or near its bottom and above the removablegratebars P, below which is an open chute P2 for directing the contentsof the chamber P into the top of the furnace-stack. The carbonic oxiddiverted through the pipe() is burned in P, air being supplied throughthe gratebars, and the contained cement material is roasted or calcinedto eliminate the carbonic acid.

In Fig. 4 the construction is in all respects the same as in Fig. 3,except that the parts O P, &e., are omitted, it being contemplated thataccording to the last way described of practicing our process the cementmaterials will be introduced directly into the furnace withoutpreliminary calcination of the earbonate of lime.

way in which this may be done.

The pipe c4 con-- The blast may be stopped when the bell is to belowered and material fed to the furnace.

We have spoken of the fused cement materials or cement clinker beingcooled and disintegrated and have illustrated in Fig. 1 a Of course thecooling may be effected in any suitable way and merely by exposure tothe atmosphere. The clinker is of course to be pulverized to producePortland cement, and the grinding or pulverizing may be effected in anysuitable way. To facilitate pulverization, we prefer to break up thecooled or solidified clinker. This may be accomplished by a spray ofwater, as indicated in the draw ings, or a solidified mass of cementclinker may be broken up in any way desired, as by crushing rolls, jaws,or stamps, and then delivered to pulverizers.

We have shown and described a vertical furnace fired with coal or coke;but it is apparent that other forms of furnaces and fuels may be usedwithout departing from the spirit of the invention.

We claim as our invention- 1. The process of making Portland cementconsisting of fusing the cement materials to a liquid mass under apressure greater than that of the atmosphere, cooling the molten massand pulverizing it.

2. The process of making Portland cement consisting of melting to aliquid the cement materials in a reducing atmosphere under a pressuregreater than that of the atmosphere, cooling the molten mass andpulverizing it.

3. The process of making Portland cement consisting in melting thecement materials in a reducing atmosphere, at the same time reducingiron oxid contained in the cement materials to the form of metalliciron, permitting the metallic iron to separate from the molten cementmaterials, drawing olf the molten cement product so depleted of iron,cooling and pulverizing it.

4. The process of making Portland cement consisting in melting thecement materials in a reducing atmosphere under pressure, at the Sametime reducing iron oxid contained in the cement materials to the form ofmetallic iron, permitting the metallic iron to separate from the moltencement materials, drawing off the molten cement product so depleted ofiron, cooling and pulverizing it.

5. The process of making Portland cement which consists in mixing thecement material with carbonaceous fuel, melting the cement materials bythe combustion of said fuel supported by an air-blast at a pressurematerially in excess of the pressure of the atmosphere, cooling themolten mass and pulverizing it.

6. The process of making Portland cement consisting of preliminarilyealcining the carbonate of lime to eliminate carbonic acid, then mixingcarbonaceous fuel with the cement ma- IOO IIO

terialsfthen maintaining the combustion of the fuelby an air-blast underpressure and thereby melting the cement materials in a ref ducingatmosphere, drawing olf the molten 5 cement product, cooling andpulverizing it.

7 The' process of making Portland cement consisting of preliminarilycalcining the car-A bonate of'lime'to eliminate carbonic acid, then.terials, then maintaining the'combustion of the fuel by an air-blastunder pressure and y thereby melting the cement materials in a reducingatmosphere ata pressure' materially greater than that of the atmosphere,drawing off the molten cement material, cooling and pulverizing it.

v8.,..The process of making Portland 'cement consisting of preliminarilycalcining'the` car# bonateof lime to eliminatie carbonic acid, thenmixing carbonaceous fuel with the cement materials,'then maintaining thecombustionof the fuel by an air-blast under pressure and.therebymeltingthe cement materials ata pressure materially greater thanthat ofthe material, cooling andpulverizing-it.l

9. The process of making Portland cement consisting of mixingthecementrnaterials with coal or coke, maintaining the combustion 5o ofsuch vfuel by an air-blast, maintaining a pressure in the presence ofthe cement materials and fuelV and adjacent tothe air-blast of from tento twenty pounds per square inch pressure, drawing'oif the molten cementmaterial, cooling and disintegrating it and pul- 10. 'lheprocess ofmaking Portland cement consisting of mixing carbonate of lime,argillaceous matter containing silica and alumina,

vmixing carbonaceous fuel with the cement ma'- 'from raw \-materialcontaining carbonate of atmosphere, drawing ofi". the molten cementabove the atmosphere, thereby melting thev cement material in an area orzone of high and'coal or coke, maintaining the combustion 55 'of suchfuel under high temperature, and a pressureof from ten to twenty poundsabove the atmosphere by means lof a high-pressure air-blast, therebydisas'sociating carbonic acid from the carbonate of lime, causing thecon, version of the carbonic acid'into carbonic'oxid in the presence ofthe highly-incandescent fuel, and also thereby melting the cementmaterialsdrawing olf the molten cement mate-v rial, cooling andpulverizing it. 12. The processof making Portland cement consisting offirst fusing carbonate of lime at a pressure greater than that of theatmosphere. then driving 0E the carbonic acid of the fused carbonate oflime -by further heating lin theV presence of silica and alumina,fusingthe silicates and aluminates of lime so produced, coolingthemolten massand pulverizing it.'

13. The process of making Portland` cement 75 lime, silica and alumina,consisting in disassociating carbonic acid from the carbonate of lime byheat, .heating the cement materials to vproduce the requisite reactionsor combinations, and converting the carbonic .acid into carbonic oxid bycontact with the incandescent carbon. Y

14. The process of making Portland cement from raw materials containingcarbonate of lime, silica and alumi'na,consisting in disas- 85 sociatingcarbonic acid from the carbonate of lime by heat, heating the cementmaterials by the aid of an air-blast to produce the requisite reactions0r combinations, converting the carbonic acid into carbonic oxid bycontact with incandescent carbon, and burning the carbonic oxid toheatthe air-blast or effect the driving of theblower.l 15. The process ofmaking Portland cement from raw materials containing carbonate of. lime,silica and alumina, consisting in"melting the cement materials (lime,silica and'alumin'a ,t .t and disassociating carbonic acid from thecar-` bonate of lime'employed bythe heat Afrom the waste gases',orproducts of combustion ofv the melting operation.y Y n 1n testimonywhereof we have hereunto sub'-y scribedour names.

EDWARD HENRY HURRY.` v HARRY JOHNSEAMAN. Q l Witnesses: v Y v GEO. A.'MERKEL`, H. B. YINGLING.-

